KumoMTA is described as 'The only true Open-Source PowerMTA alternative, capable of matching performance of several million messages per hour while providing granular traffic shaping configuration and automation across unlimited IPs' and is a Mail Server in the online services category. There are six alternatives to KumoMTA for a variety of platforms, including Linux, Mac, Self-Hosted, Amazon Web Services and Kubernetes apps. The best KumoMTA alternative is Postfix, which is both free and Open Source. Other great apps like KumoMTA are Exim, PowerMTA, MailerQ and Halon.
Postfix is a mail transfer agent (MTA) that routes and delivers electronic mail. It attempts to be fast, easy to administer, and secure. The software is also known by its former names VMailer and IBM Secure Mailer.
Exim is a message transfer agent (MTA) developed at the University of Cambridge for use on Unix systems connected to the Internet.
Email gateway application (SMTP server) that makes it easy for senders to adopt the latest authentication specifications ( SPF and DKIM) to comply with changing ISP policies for accountable outbound email delivery. No over hype. It just delivers.
United States
MailerQ is a high performance Mail Transfer Agent (MTA) and a very fast SMTP server, designed to deliver large volumes of email messages at very high speeds. MailerQ is based on RabbitMQ AMQP.
Netherlands
EU
Halon is a global leader in email infrastructure, empowering large senders and mailbox providers to maximize email. Founded in 2010, Halon's solutions process billions of emails daily worldwide.
SwedenEU
EmailSuccess, an advanced SMTP Server (MTA) built from the ground up to handle the most critical reliability, performance, security, and deliverability requirements.
ItalyEU
